Device for pivoted connection of two parts



Nov. 8, 1966 P. G. WERNER DEVICE FOR PIVOTED CONNECTION OF TWO PARTS 5 Sheets-Sheet 1 Filed Aug. 27, 1964 Nov. 8, 1966 P. G. WERNER 3,284,133 7 DEVICE FOR PIVOTED CONNECTION OF TWO PARTS Filed Aug. 27, 1964' 5 Sheets-Sheet 2 Nov. 8, 1966 P. G. WERNER 3,284,133

DEVICE FOR PIVOTED CONNECTION OF TWO PARTS Filed. Aug. 27, 1964 5 Sheets-Sheet 5 United States Patent 3,284,133 DEVICE FOR PIVOTED CONNECTION OF TWO PARTS Per Gunnar Werner, Gabelsgt. 43, Oslo, Norway Filed Aug. 27, 1964, Ser. No. 392,492 Claims priority, application Norway, Aug. 28, 1963, 12 Claims. (Cl. 297304) The invention relates to resilient hinging devices, that is devices for mechanically connecting two par-ts in such a manner that they are capable of relative rotation from a starting position while overcoming an adjustable torque exerted by a spring member.

As it is known, such resilient hinges are used to a great extent for the pivotal mounting of the back and/or the seat of furniture, especially oifice chairs. The spring member is usually constituted by one or more pressure loaded helical springs or rubber springs, leaf springs subjected to bending stress, or torsion rods. In all cases the adjustment of the torque is effected by changing the spring bias so that in order to change the torque characteristic in the increasing sense it is necessary to overcome the spring bias. Furthermost, of the known structures are more or less harmful to the appearance of the chair and many of them tend to cause unpleasant noise during the movements of the chair in use.

By means of the present invention, in a device of the type described and having a spring member acting largely tangentially to the pivotal axis the said drawbacks are avoided due to the fact that for the adjustment of the torque the spring member in the starting position is displaceable transversely to its working direction and to the pivotal axis. This solution makes it possible to achieve a compact and cheap structure by which an adjustment of the torque can be effected easily and without requiring any considerable force to be applied.

Another aspect in connection with oflice chairs is that for certain uses, namely for so-called managers chairs, a hinging by means of a so-called double mounting is required, by which the back and the seat are supported for pivotal mounting but to different extents, mostly so that the back is tilted more than the seat but both motions are interconnected. Known structures of such mountings are rather bulky and expensive. In connection with the new resilient hinging device the invention supplies a solution which can be realized with considerably less expense and by means of a mounting of much smaller dimensions, and which consists in that the support for the seat is fixed to the movable part of the device and the support for the back is pivotally mounted on the fixed part of the device for tilting about an axis extending behind and parallel to the pivotal axis of the seat, and that the back and the seat supports are movably interconnected behind the pivotal axis of the back, so that a tilting of the seat is accompanied by a greater tilting motion of the back in the desired manner. This solution is conveniently compatible with the solution referred to above with respect to the design of the actual resilient hinge.

Further features of the invention will appear from the following description of a convenient embodiment of the resilient hinge and uses for the same.

FIG. 1 is a top view of the fixed hinge member.

FIG. 2 is a view in section along the line 11-11 in FIG. 1.

FIG. 3 is :a top view of the movable hinge member.

FIG. 4 is a view in section along the line IV-IV in FIG. 3

FIGS. 5 and 6 are top and side views, respectively, of the spring member.

FIG. 7 is a view in central vertical section of the hinge used as a rockable mounting for supports for attachment to the seat of a chair.

3,284,133 Patented Nov. 8, 1966 FIG. 8 is a corresponding top view with the fixed and the movable hinge portions partly broken away and shown in section.

FIG. 9 is a sectional view corresponding to FIG. 8 and illustrating a use of the hinge as a part of a double mounting in accordance with the invention, and

FIG. 10 is a top view of FIG. 9.

The fixed hinge portion in FIGS. 1 and 2 is constituted by a bracket 1 of steel plate, largely in the form of a horizontal rectangular open-ended box, the side walls of which are extended and each provided with a circular opening 2 having its center in an axis largely in the common plane of the rear edges of the upper and the lower walls of the bracket. Welded to the bottom side 'of the bracket is a hollow mounting cone 3 providing a conical socket.

The movable fitting in FIGS. 3 and 4 consists likewise of a bracket 4 of steel plate having a yoke or web portion 5 and two downwardly projecting side walls 6, 6. At one end the side walls are extended and have eacha circular opening 7 having a somewhat smaller diameter than the openings 2 and. having its center in an axis substantially vertically below the rear edge of the yoke portion. Further, the central portion of the yoke portion 5 has a rearward extension in the form of a lug 8 which has been bent downwards and provided with an opening 9 substantially directly behind the axis of the openings 7. At their bottom edges the rear portions of the side walls 6 are curved along a circular are 10 concentric to the openings 7, and the bottom edge then continues in an inclined upward direction along a tangent 11 to the front edge of the bracket. The total height of the bracket 4 corresponds approximately to the free internal height of the bracket 1.

The spring member in FIGS 5 and 6 is composed of a series of spring elements 12 of spring steel. The spring elements are flat and generally rectangular in cross section and are generally of the shape of boomerang-like bows and are held together side by side in two groups by a holder or clip 13 consisting of two steel plate strips bent and clamped from either side around the central portions of the spring elements and fixed together fol-example by welding. In its central portion where the plate strips are interconnected the holder has a threaded bore 14. In free condition the spring elements have a height slightly exceeding the vertical distance from the bottom side of the yoke portion 5 of the bracket 4 to the lowest point of the are 10. The length of the holder 13 is less than the internal width of the bracket 4, the total width of which is in turn smaller than the internal width of the bracket 1.

These main parts are mounted together as shown in FIGS. 7 and 8. Into the openings 2 of the bnacket 1 there are inserted from the inside a pair of bearing sleeves 15 provided with flanges 16 and having a bore corresponding to the openings 7. An adjusting screw 17 with serrated head 18 is inserted into the opening 9 of the lug 8 and locked against axial displacement, whereafter t'he bnacket 4 is inserted into the bracket 1, and in corresponding positions of the openings 2 and 7 pivots 19 are then inserted from either side through the sleeves 15 and the openings 7, wherea-fter the inner ends of the pivots are welded to the adjacent side walls 6 of the bracket 4. The pivots 19, which may be tubular, are in the example shown welded to supports 20' for the seat of a chair. Finally the spring member 12, 13 is inserted with the bend facing the lug 8 so as to bear resiliently against t'he bottom side or abutment surface of the yoke 5 and the bottom or abutment surface of the bracket 1. The insertion is effected while screwing the adjusting screw 17 into the threaded bore 14 of the holder 13.

The hinge thus assembled may be placed in position by pressing the cone 3 onto, for instance, the rotatable column 21 of the bottom frame of a chair When the supports 20 have been secured to the seat of a chair, the latter can be rocked against the action of the spring elements 12 to a position shown by the dash-and-dot contour line 20 of the support 20 in FIG. 7 and defined by the engagement of the inclined edges 11 of the side walls 6 of the bracket 4 with the bottom of the bracket 1. The resilient force acting against the rocking motion is exerted by the spring elements 12 and acts with a torque, the arm of which is equal to the distance from the line interconnecting the points of engagement of the spring elements to the pivotal axis defined by the pivots 19. It is therefore possible by turning the adjustment screw 17 to change the torque arm and hence the torque exerted by the spring member. This adjustment will be effected while the chair is without load, so that the hinge is in the starting position shown in FIG. 7, in which the spring members engage plane parallel faces of the brackets 1 and 4, respectively, and at the same time have their minimum resilient stress so that the adjustment can be effected very easily.

The total width of the hinge in the axial direction can be determined at will by selecting the length of the pivots 19, and since the assembled main parts of the hinge have a very compact shape it can easily be arranged that the hinge will not be visible. If desired, it is also possible to vary the strength of the spring member by mounting more or less spring elements 12 in the holder 13.

In the double mounting in FIGS. 9 and the seat supports 20 are attached to the pivots 19 and supported exactly in the same manner as shown in FIGS. 7 and 8. However, in this case the U-shaped support or bracket 22a for the back is supported by pivots 23 in lugs 24 welded to the rear edge of the side walls of the bracket 1. Behind the pivotal axis thus define-d for the support 22a the latter is in addition movably connected to the seat supports 20 by a pair of links 25 each extending between a pivot 26 on a bracket 27 on the inner side of the adjacent seat support 20 and a transverse rod 28 inserted in the support 22a. The plane through the [axis of the pivots 26 and the rod 28 may for example be located at a distance from the axis of the pivots 19 which is substantially double the distance of this axis from that of the pivots 23. In this case, when a person using the chair leans backwards, the back of the chair will move about twice as much as the seat, and the counter-acting force of the spring member, which through the bracket 4 acts directly on the supports 20, will be further transferred from these to the back support 22a through the links 25. As appears especially from FIG. 12, the double mounting as a whole may at the same time have a compact design, above all a small width, so that it will in no way cause an unsli-ghtly appearance, and the coupling of the two motions has been effected in a very simple manner.

What is claimed is:

1. A supporting hinge structure for chairs or the like, said hinge structure comprising 'a fixed bracket, means on said bracket for mounting the same on a support, a movable bracket pivotally mounted on said fixed bracket for movement about a horizontal axis, means on said movable bracket for attaching a body supporting part of a chair, a first abutment surface on said fixed bracket disposed on one side of said axis, a second abutment surfiace on said movable bracket opposite said first surface and movable from a starting position toward said first surface upon movement of said movable bracket about said axis, spring means disposed between said surfaces to yieldably resist movement of said second surface toward said first surface, and means to move said spring means toward or away from said axis to vary the length of the lever acting on'said spring means, whereby the force resisting pivot-a1 movement of said movable bracket may be adjusted.

" 2. A supporting hinge structure as defined in claim 1 in which said second abutment surface in said starting position is substantially parallel to said first abutment surface, whereby in said starting position said spring means may be moved toward or away from said axis along said first and second surfaces with a minimum resistance to such movement.

3. A supporting hinge structure .as defined in claim 1 in which said spring means comprises a plurality of generally U-shaped spring members disposed between said first and second surfaces in side4by-side relationship and in planes disposed at substantially right angles to said axis, the free ends of said members engaging said first and second surfaces, whereby upon pivotal movement of said movable bracket said spring members are deformed substantially in said planes. 9

4. A supporting hinge structure as defined in claim 3 in which said spring members are fiat in said planes and substantially rectangular in cross section.

5. A supportnig hinge structure as defined in claim 3 and including a clip engaging said spring members to secure said spring members together as a unit.

6. A supporting hinge structure as defined in claim '5 in which said clip is disposed substantially midway of the length of said spring members.

7. A supporting hinge structure as defined in claim 5 in which said spring members are disposed in spaced groups in said clip.

8. A supporting hinge structure as defined in claim 5 in which said clip is provided with a threaded aperture and in which said means to move said spring means comprises an adjusted screw threadedly engaging said aperture and fixed against longitudinal movement in one of said brackets.

9. A supporting hinge structure as defined in claim 8 in which said fixed bracket is of generally rectangular hollow box-like formation open at opposite ends, said movable bracket being disposed within said fixed bracket and having sidewalls disposed on opposite sides of said spring means, said sidewalls being connected by a web, and a pivot fixed to each sidewall and extending outwardly through said fixed bracket to pivotally mounted said movable bracket thereon along said axis.

10. A supporting hinge structure as defined in claim 9 in which said adjusting screw is rotatably mounted in said web and fixed against longitudinal movement with respect thereto.

11. A supporting hinge structure as defined in claim 1 in which said body supporting part comprises the seat of the chair.

12. A supporting binge structure as defined in claim 11 in which an additional seatback supporting bracket is pivotally mounted on said fixed bracket for movement about a second horizontal axis spaced from said first axis, and link means .pivotally connecting said seat attaching means and said back supporting bracket, whereby upon movement of said seat attaching means about said first axis said back supporting bracket will move about said second axis a different angular distance than the movement of said seat attaching means about said first axis.

References Cited by the Examiner UNITED STATES PATENTS 163,705 5/1875 Waters 297 3o0 491,162 2/1893 Edwards 248-378 X 2,286,468 6/1942 Crameretal 297-304 3,027,191 3/1962 Lie 297-606 3,162,420 12/1964 -I .ie 248.373

FOREIGN PATENTS 154,498 5/1956 Sweden.

FRANK B. SHERRY, Primary Examiner. R. B. FARILEY, Assistant Examiner. 

1. A SUPPORTING HINGE STRUCTURE FOR CHAIRS OR THE LIKE, SAID HINGE STRUCTURE COMPRISING A FIXED BRACKET, MEANS ON SAID BRACKET FOR MOUNTING THE SAME ON A SUPPORT, A MOVABLE BRACKET PIVOTALLY MOUNTED ON SAID FIXED BRAKCET FOR MOVEMENT ABOUT A HORIZONTAL AXIS, MEANS ON SAID MOVABLE BRACKET FOR ATTACHING A BODY SUPPORTING PART OF A CHAIR, A FIRST ABUTMENT SURFACE ON SAID FIXED BRACKET DISPOSED ON ONE SIDE OF SAID AXIS, A SECOND ABUTMENT SURFACE ON SAID MOVABLE BRACKET OPPOSITE SAID FIRST SURFACE AND MOVABLE FROM A STARTING POSITION TOWARD SAID FIRST SURFACE UPON MOVEMENT OF SAID MOVABLE BRACKET ABOUT SAID AXIS, SPRING MEANS DISPOSED BETWEEN SAID SURFACES TO YIELDABLY RESIST MOVEMENT OF SAID SECOND SURFACE TOWARD SAID FIRST SURFACE, AND MEANS TO MOVE SAID SPRING MEANS TOWARD OR AWAY FROM SAID AXIS TO VARY THE LENGTH OF THE LEVER ACTING ON SAID SPRING MEANS, WHEREBY THE FORCE RESISTING PIVOTAL MOVEMENT OF SAID MOVABLE BRACKET MAY BE ADJUSTED. 